A red-tailed tropic bird covered in yellow crazy ants at Johnston Atoll National Wildlife Refuge
Stefan Kropidlowski/USFWS
Way out in the Pacific Ocean, a collection of islands in the Johnston Atoll National Wildlife Refuge offers some of the only rat-free nesting places for seabirds.
But there is still a threat facing the 15 bird species that nest there. Even in the middle of the ocean – more than 700 miles from Hawaii – an aggressive invasive species is wreaking havoc.
Yellow crazy ants were likely brought to the island by people. They have no natural predators there. And the way U.S. Fish and Wildlife spokeswoman Miel Corbett describes them, these ants sounds pretty scary – particularly for baby birds.
"They often will attack and cover the chicks when they're hatched and cause significant damage to them with their biting and stinging," Corbett said. "If you thought fire ants were bad, crazy ants are a thousand times worse."
Yellow crazy ants use formic acid to incapacitate their prey. The acid can create make the birds' eyes swell up or cause them to lose their vision, and it can even cause reproductive failure.
You can see the effects of a crazy ant attack on a chick in these before and after pictures:
A chick before a crazy ant attack. Credit: Sheldon Plentovich/USFWS
After a crazy ant attack. Credit: Sheldon Plentovich/USFWS
And, if you can stand it, you can even watch a video of a red-tailed tropic bird getting swarmed.
These seabirds nest on the ground, so they're pretty vulnerable to crazy ant attacks. So, the Fish and Wildlife Service has been using pesticides to eradicate them. After all, they're invasive, harmful to native species, and they have no natural predators on these islands. They were likely brought to the island by people. The eradication efforts have wiped out 90 percent of the ants so far.
But now another question looms. This month, the U.S. Fish and Wildlife Service instituted a new rule that will eliminate neonicotinoid pesticides on wildlife refuges in the Pacific region by 2016. That includes the Johnston Atoll refuge. The idea is protect pollinating insects such as bees from a toxic class of pesticides. But in eliminating these pesticides, the rule may also leave baby birds vulnerable to ant attacks.
Corbett said the crazy ants will likely be an exception to the new rule.
"We will be looking for an alternative," she said. "However, the crazy ants are very hardy and resistant and almost impossible to eradicate through habitat-based changes. Their aggressive nature makes them a formidable foe."
Would you make an exception to the no-neonicotinoid rule to protect seabirds from crazy ants?
-- Cassandra Profita